Rehr is a professional journalist, author and television producer from Los Angeles who has been an avid collector of antique typewriters and has written extensively on the history of office technology. Rehr collects, typewriters, ribbon tins and calculators. He is the past editor of ETCetera, the Journal of the Early Typewriter Collectors Association, and has numerous Web sites devoted to collecting antique typewriters and associated items.

Rehr's book, Antique Typewriters and Office Collectibles, was released in 1997. It is a comprehensive book with over 340 color photo illustrations.